CD00237391 Datasheet, PDF (66/177 Pages) STMicroelectronics – ARM-based 32-bit MCU, 150DMIPs, up to 1 MB Flash/128+4KB RAM

Electrical characteristics
STM32F20xxx
5.3.2
Figure 19. Number of wait states versus f_CPU and V_DD range
Wait states vs Fcpu and VDD range
8
7
6
5
1.8 to 2.1V
2.1 to 2.4V
4
2.4 to 2.7V
2.7 to 3.6V
3
2
1
0
Fcpu (MHz)
ai18748b
1. The supply voltage can drop to 1.7 V when the device operates in the 0 to 70 °C temperature range and
IRROFF is set to V_DD.
VCAP1/VCAP2 external capacitor
Stabilization for the main regulator is achieved by connecting an external capacitor to the
VCAP1/VCAP2 pins. C_EXT is specified in Table 14.
Figure 20. External capacitor C_EXT
C
66/177
ESR
R _Leak
1. Legend: ESR is the equivalent series resistance.
Table 14. VCAP1/VCAP2 operating conditions⁽¹⁾
Symbol
Parameter
MS19044V1
Conditions
CEXT
Capacitance of external capacitor
2.2 µF
ESR
ESR of external capacitor
<2Ω
1. When bypassing the voltage regulator, the two 2.2 µF V_CAP capacitors are not required and should be
replaced by two 100 nF decoupling capacitors.
Doc ID 15818 Rev 9